Machinery Lubrication magazine published by Noria Corporation
Issue link: https://www.e-digitaleditions.com/i/1103301
54 | March - April 2019 | www . machinerylubrication.com BACK PAGE BASICS to a lubricant's film thickness. ese particle sizes cause the most damage to moving surfaces and thus should be closely monitored. e method used to calibrate the automatic particle counter should also be considered. is rarely will be presented in any oil analysis report, so you will need to contact your lab or equipment manufacturer to find out which ISO calibration standard was employed. Again, the most current calibration standard is ISO 11171. SAE AS4059F While ISO 4406:87 and 4406:99 have been widely accepted, there is still a signifi- cant portion of industries and countries that use SAE AS4059. Several revisions have been made to this standard over time. e most current revision of this standard occurred in September 2013, which is SAE AS4059F. e reporting of this standard utilizes the same table as the NAS 1638 standard shown. The most current revision has added optional reporting methods to include the ability to report on the specified cumulative particle size count instead of a single code that represents the cleanliness of the oil. You will be able to identify if the code is specific to a cumulative particle size count by a suffix letter after the class. e letter will be between A-E and will tell you what cumulative particle size count category the code represents. For example, a Class 6B would indicate how many particles are greater than 5 microns (optical microscope) or 6 microns (most APCs). Be careful, though, as the revision of AS4059 may result in different cleanliness classes from those obtained with previous versions whenever the class was specified without any letter size suffix and in some cases when the class was specified with a suffix. Cleanliness classes with no suffix from NUMBER OF PARTICLES PER mL More than Up to and Including Range Number 5,000,000 10,000,000 30 2,500,000 5,000,000 29 1,300,000 2,500,000 28 640,000 1,300,000 27 320,000 640,000 26 160,000 320,000 25 80,000 160,000 24 40,000 80,000 23 20,000 40,000 22 10,000 20,000 21 5,000 10,000 20 2,500 5,000 19 1,300 2,500 18 640 1,300 17 320 640 16 160 320 15 80 160 14 40 80 13 20 40 12 10 20 11 5 10 10 2.5 5 9 1.3 2.5 8 0.64 1.3 7 0.32 0.64 6 0.16 0.32 5 0.08 0.16 4 0.04 0.08 3 0.02 0.04 2 0.01 0.02 1 (1) >1 μm >5 μm >15 μm >25 μm >50 μm >100 μm (2) >4 μm >6 μm >14 μm >21 μm >38 μm >70 μm Size Code Classes A B C D E F 000 195 76 14 3 1 0 00 390 152 27 5 1 0 0 780 304 54 10 2 0 1 1560 609 109 20 4 1 2 3120 1217 217 39 7 1 3 6250 2432 432 76 13 2 4 12500 4864 864 152 26 4 5 25000 9731 1731 306 53 8 6 50000 19462 3462 612 106 16 7 100000 38924 6924 1224 212 32 8 200000 77849 13849 2449 424 64 9 400000 155698 27698 4898 848 128 10 800000 311396 55396 9796 1696 256 11 1600000 622792 110792 19592 3392 512 12 3200000 1245584 221584 39184 6784 1024 An ISO 4406 Chart SAE AS4059 Rev. E (Cleanliness Classes for Cumulative Counts – Particles per 100 mL) (1) Size range, optical microscope, based on longest dimension as measured per ARP598 or APC calibrated per ISO 4402:1991 (2) Size range, APC calibrated per ISO 11171 or electron microscope, based on project- ed area equivalent diameter (3) Classes and contamination limits identical to NAS 1638